When finding the navigation node to activate for a given url, our navigation
system does not evaluate as a tree of nav nodes. Instead it evaluates the best
node by checking against a map of nav nodes whose keys are urls.
So, what if we had a piece of navigation that has an acl preventing the user
from seeing that nav node. If the nav nodes were evaluated as a tree, than all
of the nodes under that nav node would "inherit" the acl because that entire
section of the tree wouldn't be viewable. Instead, if a user enters a url that
corresponds to a nav-node under the acled node, they would see an activated node
for the url that they typed, but it would not show the parent node.
The work-around is to add the parent's acl to every child node.
See the screenshot.